A wireless, wearable, battery-free multi-sensory system is essential for continuous, non-invasive real-time monitoring of multiple physiological parameters, enabling seamless, discreet healthcare. The main bottleneck in developing such systems lies in achieving low power consumption to enable battery-free operation, while maintaining reliable, high-frequency data acquisition and efficient wireless communication with a skin-impedance-matched antenna within a compact, wearable form factor. To overcome this, we integrate energy-harvesting technologies with high-precision multiple sensors and a flexible, skin-compatible antenna system into a single platform, enabling battery-free operation with efficient data transmission and reception. Our multi-sensory system experimentally demonstrates successful skin-mountable monitoring of ECG, SpO 2 , and temperature at a sampling rate of 70 Hz, with data wirelessly transmitted via Bluetooth Low Energy, all powered by a radio-frequency energy-harvesting antenna. Beyond personal health tracking, this technology also holds great potential for remote patient monitoring in chronic disease management, empowering healthcare providers with continuous access to real-time patient data for timely and uninterrupted data acquisition. Typically, health monitoring systems depend on separate hardware for each physiological signal—such as electrocardiogram, pulse oximetry, and temperature—which requires bulky setups with complex wiring, limiting their practicality for wearable and continuous use. These limitations significantly hinder proactive and long-term monitoring beyond clinical settings. Here, a fully integrated, skin-mountable multisensory patch designed for chest application is demonstrated. The system simultaneously acquires electrocardiogram (ECG), pulse oximetry, and temperature signals, powered sequentially via a battery-free near-field communication (NFC) antenna. Furthermore, high-frequency, noise-free data transmission is achieved through a skin-impedance-matched flexible Bluetooth antenna, ensuring seamless communication without compromising user comfort. This compact, wireless system makes it possible to monitor vital physiological parameters remotely and in real time, helping with early diagnosis, ongoing care, and preventive health tracking outside clinical environments. Fig. | Conceptual illustration of a battery-free, skin-mountable wearable patch. The system enables simultaneous energy harvesting and data transmission through an integrated flexible NFC and Bluetooth antenna. • Integration of Electrocardiogram, pulse oximetry, and temperature sensing into a single flexible and skin-conformal patch for comprehensive physiological monitoring. • Battery-free operation through sequential powering enabled by an embedded NFC antenna for wireless energy harvesting. • Flexible Bluetooth antenna matched to skin impedance for robust and noise-free wireless transmission in real-time. • Optimized system for short-range wireless data transfer (1–10 m), enabling real-time smartphone visualization and cloud connectivity. • Demonstration of consistent signal quality across ECG, SpO₂, and temperature, benchmarked against commercial devices.

Locomotion in Virtual Reality (VR) is a key factor in determining user immersion and comfort. Thus, various locomotion methods in VR while seated have been explored. While controller-based seated locomotion is widely used due to its simplicity and low physical effort, it often lacks embodied motion cues, reducing immersion. On the other hand, seated walking-in-place (WIP) techniques enhance immersion through body-based interaction but can introduce significant physical fatigue. In this paper, we propose Leg-swing, a novel foot-based seated VR locomotion interface designed to balance immersion and physical load. Users swing their legs forward and backward to move through virtual environments, mimicking the rhythm of walking without high physical load. The system uses a high-resolution pressure sensor embedded in the seat to infer locomotion speed and leaning angle without the need for wearable sensors. Through a user study comparing Leg-swing to joystick and seated WIP that utilize marching motions, we found that Leg-swing was perceived to provide significantly higher immersion than joystick-based locomotion with similar physical effort, and users reported significantly lower physical load than seated WIP while maintaining comparable perceived immersion. These results suggest that Leg-swing offers a promising middle ground between immersion and physical load for seated VR locomotion.

Longitudinal improvements in comfort, mobility, and quality of life with adjustable-volume prosthetic sockets.

3D printed trichome-inspired permeable bioadhesive for wearable bioelectronics

Leather is highly susceptible to microbial colonization due to its moisture retention and nutrient-rich structure, which promotes bacterial and fungal growth and compromises hygiene, durability, and user comfort in applications such as footwear and upholstery. In this work, tellurium nanoparticles (TeNPs) were green synthesized through redox reaction using plant extract and structurally characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) to confirm crystalline phase, particle size, and morphology. The TeNPs were then applied to leather substrates to generate antimicrobial leathers. The distribution and surface morphology of TeNPs on leather were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) to verify nanoparticle anchoring and elemental composition. Mechanical performance was assessed through tensile strength and elongation testing to evaluate the influence of TeNP incorporation on the integrity of the leather matrix. Antibacterial and antifungal activities of TeNP-treated leather were quantified against representative Gram-positive and Gram-negative bacteria and Aspergillus fungal. The antimicrobial efficacy of TeNPs is attributed to ROS generation, disruption of microbial cell membranes, inhibition of thiol-containing respiratory enzymes, and Te redox cycling-mediated oxidative stress, which together achieve broad-spectrum inactivation of bacterial and fungal pathogens. The TeNP-functionalized leather exhibited pronounced antibacterial and antifungal activities while enhancing mechanical performance, indicating its potential as a high-value, hygienic leather material for advanced footwear and other consumer applications.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-026-57078-0.

Steady-state visual evoked potential brain–computer interfaces offer a high-speed communication channel. However, traditional steady-state visual evoked potential paradigms often rely on strong flickering visual stimulation, which can lead to substantial visual fatigue. Moreover, the electroencephalography responses evoked by brightness flicker are spatially constrained and are primarily associated with occipital visual processing. This study presents a novel text sequence stimulation paradigm that combines periodic visual stimulation with orthographic information and elicits distinct occipital and occipitotemporal scalp response patterns relative to conventional brightness flicker. Frequency-sweep experiments were conducted to investigate the temporal, spatial, and spectral characteristics of the evoked responses. A comparison experiment further showed that text sequence stimulation is less sensitive to variations in stimulus size and luminance than conventional brightness flicker. Based on these findings, a 40-target speller was developed and validated through online experiments. The proposed paradigm achieved an information transfer rate of 235.12 ± 30.12 bits/min while significantly improving user comfort, as confirmed by questionnaire evaluations. These results suggest that text sequence stimulation offers a practical design direction for high-speed and more comfortable visual brain–computer interface.

Assessment framework for social aspects of sustainable building

Assessment and improvement strategies for distribution grid capacity considering distributed energy resources and electric vehicles

Day-ahead optimization model for renewable energy communities considering load shifting, electric vehicles and vehicle-to-grid technology

BackgroundTraditional vehicle-repairing carts in India present ergonomic challenges and occupational health and safety issues. Operators experience discomfort and strain due to difficulties in pushing the cart over long distances and in organising tools and setting up workstations.ObjectivesTo redesign the makeshift vehicle repairing cart by incorporating ergonomic principles and relevant anthropometric data of target users, aiming to reduce physical fatigue and improve usability.MethodsErgonomic evaluations were conducted to identify areas of discomfort, focussing on body parts affected. The operators expressed postural discomfort in different parts of the body like the lower back, neck, shoulder, forearm, wrist, ankle, and foot.ResultsResearchers made recommendations for the proper layout of the tools, provision for manipulating the vehicle in a better manner with ergonomically designed handles, and provision of a modular workstation detachable from the main unit. Accordingly, three concept prototypes were suggested.ConclusionThe manufacturer adopted all three concepts in principle for the new design to improve ergonomics and design of cart for user comfort.

Streamlined custom manufacturing for optimized 3D printed prostheses through 3D pressure mapping.

Accurate sleep assessment relies on the high-quality, long-term acquisition of physiological signals. However, traditional polysomnography (PSG) relies on cumbersome equipment with poor user comfort and often interferes with the user's sleep quality. Herein, a wearable in-ear EEG sleep monitoring and intervention platform is developed based on a poly(3,4-ethylenedioxythiophene) (PEDOT)/leather composite electrode. By leveraging the relatively enclosed and stable environment of the ear canal, this platform achieves an optimal balance between long-term comfort and signal accuracy. The PEDOT/leather electrode demonstrates robust electrical stability, low interfacial impedance, and high mechanical durability. Benefiting from the anatomical proximity to the central nervous system, the platform enables precise EEG acquisition and sleep stage classification (Wake, NREM, REM). Moreover, active sleep modulation is realized through integrated closed-loop acoustic stimulation. This integrated sensing-and-intervention platform offers a highly promising solution for next-generation personalized sleep medicine and neurological disease management.

Virtual reality (VR) is increasingly used in public speaking training, yet the distinct roles of environmental context and virtual audience design remain unclear. This study examines how avatar visual style (realistic vs. stylized) and scene type (natural vs. indoor) influence subjective experience and physiological stress. A total of 132 participants were assigned to a 2 × 2 between-subjects experiment. Subjective experience was assessed using standardized questionnaires, while physiological responses were measured via electrodermal activity and heart rate variability, complemented by post-experiment interviews. Results revealed a dissociation between subjective and physiological responses. Natural environments significantly enhanced user satisfaction and overall experience, whereas avatar style primarily influenced physiological stress. Specifically, stylized avatars elicited lower electrodermal activity than realistic avatars, indicating reduced sympathetic arousal. No significant interaction effects were observed. Mediation analyses showed no significant roles of perceived support or threat, suggesting that physiological responses may not rely on explicit cognitive appraisal. Qualitative findings further indicated that ambiguous audience feedback limited evaluative interpretation. These findings support a dual-pathway framework in which environmental context shapes cognitive–affective experience, whereas avatar realism modulates implicit physiological stress. This study provides theoretical insights and practical implications for designing VR systems that enhance user comfort and reduce stress.

ABSTRACT This paper presents the development of a passive, non‐articulated foot orthosis by integrating 3D scanning and 3D printing technologies, following a comprehensive analysis of existing orthotic solutions available on the market. The proposed methodology begins with the precise capture of the foot's anatomical geometry through 3D scanning, enabling a customized fit and enhanced user comfort. The acquired data is then processed in specialized 3D modeling software to generate a digital orthosis model, which is subsequently fabricated using additive manufacturing. This workflow offers an efficient and cost‐effective approach to producing personalized orthopedic devices. The final physical prototype shall be tested, in future studies, by a user to assess both the geometric fit and comfort level during ambulation. The results underscore the potential of combining 3D scanning, CAD modeling, and 3D printing in the development of customized orthopedic solutions, emphasizing the advantages of personalization, rapid prototyping, and reduced production time. Future studies are intended to evaluate the structural performance of the design; the digital model might undergo Finite Element Analysis (FEA) under simulated loading conditions corresponding to normal walking dynamics. This paper aims to conduct a thorough study of existing ankle‐foot orthoses, as well as to create such an orthosis using 3D scanning and 3D printing, and to perform a biomechanical analysis on the final prototype.

This paper explores the structural design and material application of seating systems in science museums, focusing on safety and ergonomic comfort. To address the requirements of modern exhibition environments, the study employs finite element analysis (FEA) and body pressure distribution experiments to evaluate the mechanical performance and user comfort of four distinct seat structures and materials: polyurethane, polyester fiber, polypropylene foam, and memory foam. The investigation analyzes their effects on stress distribution, strain, and pressure relief. Results indicate that while structural design is critical for ensuring uniform stress distribution, material properties primarily dictate comfort and pressure alleviation. Specifically, memory foam and polyurethane demonstrate the optimal balance between comfort and load-bearing capacity, whereas polypropylene presents risks of localized stress concentration. Consequently, the study proposes a "structural optimization coupled with material matching" strategy, utilizing rigid materials for load-bearing and flexible materials for comfort interface. These findings provide practical guidance for the engineering design and material selection of public seating in science museums.

The increasing penetration of residential photovoltaics (PV), energy storage, and flexible demand introduces significant uncertainty, coordination challenges, and long-term asset degradation in smart energy communities. Existing residential energy management approaches often rely on deterministic optimization or single-agent learning, limiting robustness, scalability, and the ability to balance economic performance, asset health, and user comfort under stochastic operating conditions. This paper proposes a unified, practically oriented integration of uncertainty, asset degradation, comfort constraints, and peer-to-peer (P2P) energy exchange within a multi-agent reinforcement learning (MARL) framework for residential energy communities. The community is formulated as a Markov game in which each prosumer operates as an autonomous agent with PV generation, battery storage, and flexible demand. Economic cost, comfort preservation, and asset degradation are incorporated into a single learning objective. This enables decentralized and coordinated decision-making through shared interactions with the environment. Simulation results under varying levels of uncertainty and community sizes demonstrate that the proposed framework achieves performance competitive with a centralized benchmark while exhibiting consistent performance, reduced asset degradation, and effective comfort preservation.

Introduction Today, the rapid acceleration of urbanization has made it necessary to reconsider the balance among energy consumption, environmental sustainability, and quality of life. Buildings, which account for a significant share of cities’ carbon footprint, play a critical role in efforts to improve energy efficiency and ensure user well-being. In this context, advances in digitalization and Internet of Things (IoT) technologies have enabled buildings to evolve beyond mere physical structures into dynamic, data-driven, and user-interactive systems. Within this framework, the present study constitutes a systematic literature review addressing the effects of indoor environment design in smart cities on energy efficiency (E), user comfort (C), and environmental sustainability (S). In recent years, IoT-based sensor and control technologies have reconfigured approaches to energy management in buildings by enabling the continuous monitoring of environmental parameters such as temperature, humidity, carbon dioxide levels, lighting, and movement, while also strengthening user experience through a holistic perspective. Methods In this regard, the study examined 76 different works in the literature, including field applications, experimental research, and conceptual models. These studies were evaluated through an inductive thematic analysis approach based on content and classified according to recurring conceptual clusters in the literature. Results An examination of these sources reveals that the contributions of IoT technologies to smart buildings and cities are multidimensional in nature. This extensive body of knowledge in the literature demonstrates that IoT is not merely a technical infrastructure but also an ecosystem that transforms energy, health, the environment, transportation, and social life. It is evident that the data derived from all reviewed studies were synthesized under the headings of energy efficiency, indoor environmental quality and comfort, smart city infrastructure, user interaction, security/facility management, and industrial applications. Accordingly, the present study evaluates the contributions of IoT-based solutions to reducing energy consumption, improving environmental conditions, and supporting user-centered indoor design. The reviewed studies show that these technologies not only enhance energy efficiency (maximum savings: smart parking [92.6%] and smart lighting [73.2%]; average building savings: 20–30% through BEMS and IoT systems; HVAC optimization: 30–70% through artificial intelligence), but also support user health and comfort (the use of smart systems is generally expected to produce an improvement of more than 20% in comfort levels, while this rate can reach the 70–90% range with advanced personalized models). Furthermore, they demonstrate that IoT-based systems play a strategic role in achieving environmental sustainability goals, reducing carbon emissions, and implementing smart city policies. Discussion The original contribution of this study lies in its systematic synthesis of energy, comfort, and sustainability within an integrated thematic classification framework, thereby revealing trends in the field, research gaps, and potential future directions.

Bicycle infrastructure preferences vary by user experience and comfort, but evidence suggests both cyclists and drivers perceive separated bike lanes as safer than shared lane markings (sharrows). Little is known about sharrows impact in real-world settings, as no observational studies have evaluated their before and after installation impact. Santa Ana, California, incorporated sharrows into its active transportation plan to increase and encourage safe riding in a downtown commercial corridor where separated bike lanes were not feasible. Researchers conducted a natural experiment using a pre-post study design, collecting baseline data in 2015 before installation, and follow-up data in 2016 and 2017. A total of 54 hours of direct bicycle observation was conducted across two target areas over three years (2015 – 2017). A modest increase in bicycling was observed from 2015 to 2016, but was not sustained into 2017. Sidewalk and wrong-way riding increased slightly over time, while participation by female riders and older adults (65+) declined post-intervention. Sharrows offer a low-cost, scalable approach for promoting road sharing and guiding cyclists toward safer positioning, particularly in resource-constrained urban areas. This study’s real-world evaluation underscores the importance of tailoring active transportation infrastructure to meet safety and accessibility needs for all. Findings suggest sharrows are effective when paired with complementary strategies, such as targeted education, driver awareness efforts, or enhanced infrastructure, to better serve diverse populations and promote long-term engagement in bicycling. Further research can build on these insights by integrating user-centered evaluation methods and emerging data technologies.

Virtual reality (VR) enables interactions beyond real-world limitations, yet many such capabilities remain underexplored due to concerns about user comfort and increased disorientation and cybersickness. This study examined how altering the user's virtual pitch orientation influences interaction performance and subjective ratings. In a within-subject design, 30 seated participants experienced 12 virtual tilts from moderate to extreme (±180°). We assessed comfort, simulator sickness, perceptual responses, and performance. Our results revealed no significant increases in nausea, disorientation, or decreased comfort, with mild tilts performing equivalently to baseline. Notably, even extreme tilts maintained low nausea levels. Performance effects were mixed: forward tilts yielded similar or slightly improved performance, whereas backward tilts modestly impaired performance, though not significantly. These findings suggest that VR experiences featuring virtual body orientations distinct from the user's physical posture are feasible without compromising comfort or performance, enabling novel opportunities in simulation, interface design, visualization, creative content creation, and VR gaming.

State-of-charge-aware charging opportunity detection for electric vehicles using data-driven learning and digital twin simulation